The present invention relates to vehicle seat slides for use in vehicle seat assemblies, and more particularly to such seat slides having a single track lock-up position.
Multi-seat vehicles, such as vans, minivans, sport utility vehicles, and the like, typically have middle (second row) and perhaps rear (third row) vehicles seats that are placed rearwardly of the driver""s and front passenger""s (first row) vehicle seats. In some such vehicles, there is not direct access by means of an adjacent door to the third row seats or the cargo area behind the second row seats, or to the second row seats in vehicles having only one door on each side. In this instance, many vehicles have an xe2x80x9ceasy entryxe2x80x9d (sometimes referred to in the art as an xe2x80x9cE-Zxe2x80x9d entry) feature, wherein the track slides of the first row vehicle seat assembly or the second row vehicle seat assembly, as is the case, are unlocked and the seat assembly is moved longitudinally forwardly from an occupiable position located aft of the track lock-up position to an unlocked access position located fore of the track lock-up position, as the seatback member is forwardly folded over the seat cushion member.
To achieve this unlocked access position in the prior art, the seatback latch is released and the seatback member is thereafter folded forwardly over the seat cushion member. Further, both the inboard and outboard movable track members of the vehicle seat slide are automatically unlocked, with respect to their fixed track member, and are caused to slide forwardly along their respective fixed track members by a biasing spring, until the vehicle seat assembly reaches a forwardly displaced, unlocked vehicle access position. When use of the seat assembly is again required, the backrest of the vehicle seat assembly is returned to its generally upright configuration, and the seat assembly is slid rearwardly to the vicinity of its starting position, whereat the inboard and outboard and movable track members again lock-up with their respective fixed track members to secure the seat assembly in place within the vehicle.
In order to return the prior art vehicle seat assembly rearwardly to the track lock-up position as aforesaid, it is common to push on the outboard portion of the backrest of the vehicle seat assembly, since the outboard portion is within easy reach of a person outside the vehicle. Accordingly, the outboard movable track member tends to become disposed slightly rearwardly relative to the inboard side movable track member, largely due to the stacking of tolerances in the vehicle seat slide and related track lock mechanism. In this instance, there is a significant chance that the outboard movable track member of the vehicle seat slide will lock first, and the inboard movable track member will not quite reach its lock-up position, and thus will remain unlocked. Such single sided locking of the vehicle seat slide is quite dangerous in any situation where rapid deceleration is involved, such as an accident situation, as there is a chance that the vehicle seat assembly could break loose from such single sided locking and slide forwardly in an unconstrained manner.
The above-noted safety concern is not as critical in a prior art vehicle seat slide that can be locked in any one of a plurality of seat slide lock-up positions, as there is a locking redundancy, such that there is a chance that the vehicle seat slide could lock in any one of a more forward or a more rearward locking position so as to prevent unexpected release of the track lock mechanism assembly. However, in prior art vehicle seat slides having a single track lock-up position, there is no chance of a seat slide locking in such a more forward or rearward locking position, as no redundant lock-up positions exist. Therefore, it is especially important in vehicle seat slides having a single track lock-up position (such as, for example, a vehicle seat slide incorporating an easy entry feature) that the inboard and outboard movable track members must both lock whenever the vehicle seat assembly is slid rearwardly past the track lock-up position.
In order to ensure the locking of both the inboard and outboard movable track members at the track lock-up position, it has been found useful to slide the vehicle seat assembly evenly, and not in a longitudinally uneven skewed manner, thus precluding one movable track member from reaching the track lock-up position before the other movable track member.
Another reason that both the inboard and the outboard track lock mechanisms might not lock upon return of the vehicle seat assembly from a forward easy entry position to its track lock-up position, is the stacking of tolerances of the various components of the movable and fixed track members and of the track lock mechanisms. Such tolerances, or in the other words the variation in the size of the components of the movable and fixed track members and the track lock mechanisms, can cause the inboard and outboard track lock mechanisms to be longitudinally misaligned when the vehicle seat assembly is being returned to its design position, thus making concurrent locking of both of the track lock mechanisms difficult.
Therefore, it is an object of the present invention to provide for use with a vehicle seat assembly, a seat slide that ensures that both the inboard and outboard movable track members of the seat assembly are locked in place upon return of the vehicle seat assembly from a forwardly displaced unlocked access position to a rearwardly displaced track lock-up position.
It is a further object of the present invention to provide a vehicle seat slide having a single track lock-up position for use in a vehicle seat assembly having an easy entry feature, wherein the vehicle seat slide precludes single sided locking of the inboard and outboard movable track members upon return of the vehicle seat assembly from the forwardly displaced unlocked access position to the rearwardly displaced track lock-up position.
It is another object of the present invention to provide a vehicle seat slide having a single track lock-up position for use in a vehicle seat assembly having an easy entry feature, which vehicle seat slide minimizes the effect of the stacking of tolerances on the locking of both the inboard and the outboard movable track members upon reaching their respective track lock-up positions.
In accordance with the present invention there is disclosed a vehicle seat slide for use with a vehicle seat assembly mounted thereon. The vehicle seat slide comprises a movable track member slidably engaging a fixed track member for longitudinal sliding movement of the movable track member relative to the fixed track member along a longitudinal axis between a rearward track position, an intermediate track position, and a forward track position. A track locking means is mounted on one of the fixed and movable track members and has one or more detent portions selectively engageable with a corresponding number of slots formed on the other of the fixed and movable track members to respectively receive, in blocking engagement, one each, the one or more detent portions in generally transverse relation to the longitudinal axis, so as to define a locking configuration of the track locking means, at which locking configuration the longitudinal sliding movement of the movable track member relative to the fixed track member is restrained. The track locking means further comprising a biasing means adapted to bias the track locking means toward the locking configuration. An actuator means is mounted on the movable track member in operative connection with the track locking means for movement between an actuating configuration whereat the actuator means urges the track locking means away from the locking configuration against the action of the biasing means, and a rest configuration whereat the actuator means permits the track locking means to move toward the locking configuration. A control means is operatively mounted on the fixed track member for co-operative contact of the control means and the actuator means so as to cause the actuator means to be held in the actuating configuration upon the movable track member being moved to the forward track position and for thereafter permitting the actuator means to return to the rest configuration only after movement of the movable track member to a position rearward of the intermediate track position.
Other advantages, features and characteristics of the present invention, as well as methods of operation and functions of the related elements of the structure, and the combination of parts and economies of manufacture, will become more apparent upon consideration of the following detailed description and the appended claims with reference to the accompanying drawings, the latter of which is briefly described hereinbelow.